The Minnesota CHEAR Exposure Assessment Hub brings together highly talented investigators from the University of Minnesota and the Minnesota Department of Health with broad and internationally recognized expertise in the identification and analysis of agents that are potentially harmful to human health, including children's health. Our team is unique because our scientists have years of experience in the development and application of state-of-the-art high throughput analytical chemistry methods based mainly on mass spectrometry for the assessment of trace amounts of targeted toxicant or carcinogen metabolites in large clinical and epidemiological studies, with all appropriate sample tracking and quality control methods in place. They have also developed and applied methods for the untargeted analysis of human serum, urine, or fecal samples as well as the analysis of DNA adducts and other biological response parameters in samples from humans. Therefore, we can provide children's health researchers with access to state-of-the-art infrastructure for both targeted and untargeted analysis of biological samples as well as characterization of biological responses associated with those exposures. This goal is firmly embedded within the concept of the exposome and its relationship to children's health. The resources and cores within this Hub are as follows: The Targeted Analysis Resource will use predominantly high throughput mass spectrometric methods with well-established quality control procedures to provide timely and reliable quantitative data relevant to 3 major areas of potential importance with respect to children's health: exposure to general environmental toxicants and carcinogens; exposure to tobacco-specific compounds; and variations in levels of endogenous and dietary compounds. The Untargeted Analysis Resource will conduct high resolution mass spectrometry-based untargeted metabolomics to examine the chemical composition of diverse biological samples relevant to children's health. The Biological Response Indicators Resource will conduct state-of-the-art analyses of carcinogen-DNA adducts, biomarkers of oxidative damage including DNA adducts, biomarkers of inflammation, and parameters of epigenetic modification. The Developmental Core will develop new high throughput methods to quantify organophosphate pesticides, herbicides, and insecticides in urine as well as their adducts to serum albumin, and will establish a multi- residue approach to bio-monitor relevant chemicals in hair. The Administrative Core will coordinate all activities within the Minnesota CHEAR Exposure Assessment Hub and serve as the link between our Hub and the CHEAR Coordinating Center.